Polycystic kidney disease is a genetic disorder in which multiple fluid-filled cysts develop in the kidneys, and elsewhere in the body. Polycystic kidney disease can be inherited as autosomal recessive (ARPKD) or autosomal dominant (ADPKD). Autosomal dominant polycystic kidney disease is caused by mutations in the PKD1 or PKD2 gene. ADPKD is a progressive disease in which cyst formation and renal enlargement lead to renal insufficiency and eventually end-stage renal disease in 50% of patients by age 60. ADPKD patients may require lifelong dialysis and/or kidney transplant. There is currently no approved therapeutic agent for treating ADPKD.